This invention is related to a high solids coating composition and in particular to a high solids coating composition that dries rapidly and cures at ambient temperatures.
Manufacturing industries are in need of coating compositions that have a high resin solids content to meet reduced solvent emmissions requirements, that dry and cure at ambient temperatures and thereby conserve energy, that dry rapidly to a tack-free finish so that a coated article can be further processed, and that form cured finishes that have good physical properties. Conventional alkyd resin coating compositions generally do not have a high solids content and do not dry rapidly at ambient temperatures.
Coating compositions of acrylic-alkyd resins such as those shown in Miller et al. U.S. Pat. No. 3,585,160 issued June 15, 1971 in which drying oil fatty acid esters are attached to an acrylic segment by a vinyl oxazoline ester generally do not have a high solids content since the polymers used therein have a relatively high molecular weight. Coating compositions of acrylic-alkyd polymers in which drying oil fatty acids are attached to an acrylic segment through a glycidyl functionality, such as glycidyl methacrylate, generally do not have a high solids content since the molecular weight of the polymer is usually high caused by side reactions that occur during formation of the acrylic-alkyd polymer.
The novel coating composition of this invention meets the aforementioned needs, has a high resin solids content, dries rapidly to a tackfree finish, cures at ambient temperatures and forms a finish that has good physical properties such as a high gloss, water spot resistance, resistance to humidity, excellent adhesion to metal substrates and good hardness.